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U.S. Roads: South Dakota Mid‑importance This article is within the scope of the U.S. Roads WikiProject, an attempt to build a comprehensive and detailed guide to state highways and other major roads in the United States. If you would like to participate, you can edit the article attached to this page, or visit the project page, where you can join the project and/or contribute to the discussion.U.S. RoadsWikipedia:WikiProject U.S. RoadsTemplate:WikiProject U.S. RoadsU.S. road transport articles Mid This article has been rated as Mid-importance on the project's importance scale. Locations   South Dakota   This article has a map. If the file has an error, please work with the Maps department to correct it. This article has a junction list compliant with the Manual of Style on road junction lists. This article has a KML file. If the file has an error, please work with the Maps department to correct it.   South Dakota Mid‑importance This article is within the scope of WikiProject South Dakota, a collaborative effort to improve the coverage of the U.S. state of South Dakota on Wikipedia. If you would like to participate, please visit the project page, where you can join the discussion and see a list of open tasks.South DakotaWikipedia:WikiProject South DakotaTemplate:WikiProject South DakotaSouth Dakota articles Mid This article has been rated as Mid-importance on the project's importance scale.

Is the 250-mile figure exact or rounded off? In the article, the metric equivalent is given as 402 km, meaning that the 250-mile figure is exact. In the infobox, however, the metric measure is given as 400 km, meaning that the 250 is inexact. Which is the case? 169.199.121.2 ( talk) 16:55, 22 October 2012 (UTC) reply

It's not cited. Therefore it's approximate. At WP:USRD, pretty much every article with an exact mileage has a source for that mileage. The mileage is also usually a decimal, and not a rounded number. – TC N7 JM 12:04, 24 November 2012 (UTC) reply

More than a year later, I've found the exact length. T C N7JM 20:23, 23 December 2013 (UTC) reply